This invention relates in general to axle assemblies for vehicles and in particular to an improved structure for positively retaining a spindle which is press fit into a hollow tube portion of a housing for such an axle assembly.
Axle assemblies are well known structures which are in common use in most vehicles. Such axle assemblies include a number of components which are adapted to transmit rotational power from an engine of the vehicle to the wheels thereof. These rotatable components are usually enclosed in a protective non-rotatable axle housing. Typically, the axle housing includes a central carrier portion having a pair of hollow tube portions extending outwardly therefrom. A differential is rotatably supported within the carrier portion of the axle housing, while a pair of rotatable axle shafts are enclosed within and extend through the tube portions. The differential is connected between an input drive shaft extending from the vehicle engine and the pair of output axle shafts. The axle shafts extend through the tube portions to rotatably drive wheels of the vehicle. Thus, the carrier portion and the tube portions form a housing for the axle assembly, inasmuch as the differential and the axle shafts are supported for rotation therein.
A typical axle housing further includes a pair of hollow spindles which are connected to the outer ends of the tube portions. The spindles are adapted to support the wheels of the vehicle thereon for relative rotation, usually by means of tapered roller bearings. For the sake of economy, the spindles are generally not formed integrally with the other portions of the axle housing. This is because the spindles must withstand the wear caused by supporting the vehicle wheels thereon. As a result, the spindles are usually formed from a higher grade (and, consequently, more expensive) material than the carrier portion and the tube portions of the axle housing, which are not subjected to such wear.
In non-steering axles, the spindles are directly connected to the tube portions of the axle housing. To accomplish this, the inner ends of the spindles are typically inserted telescopically within the outer ends of the tube portions. Frequently, the spindles are then permanently secured to the tube portions, such as by friction welding, so as to prevent the removal thereof. However, in some instances, it is desirable to permit removal of the spindles from the tube portions. In those instances, the spindles are typically press fit into the tube portions so as to provide a frictional engagement which prevents the removal thereof during normal operating conditions.
In those axle housings which provide removable spindles, it has been found desirable to provide a positive retainer for preventing the spindles from being removed from the tube portions under unusual operating conditions. Several positive spindle retaining structures are known in the art. However, it has been found that such known structures are relatively expensive to produce because of the amount of material required to effect a reliable retainment of the spindles or because of difficulties in manufacture and assembly. Accordingly, it would be desirable to provide an improved positive spindle retaining structure for a vehicle axle housing which simpler and less expensive to manufacture and assemble than known structures.